日期:2014-05-18 浏览次数:20748 次
--> 测试数据:[test]
if object_id('[test]') is not null drop table [test]
create table [test]([name] varchar(3),[type] varchar(1))
insert [test]
select 'sun','A' union all
select 'cat','B' union all
select 'dog','B' union all
select 'mon','A' union all
select 'fri','A' union all
select 'red','C'
declare @str varchar(50)
set @str=''
;with t
as(
SELECT *FROM (SELECT DISTINCT [type] FROM [test])A
OUTER APPLY(
SELECT [name]= STUFF(REPLACE(REPLACE(
( SELECT [name] FROM [test] N
WHERE [type] = A.[type]
FOR XML AUTO
), '<N name="', ','), '"/>', ''), 1, 1, '')
)N
)
select @str=@str+';'+[type]+':'+name from t
select right(@str,len(@str)-1) as value
/*
value
----------------------------------------
A:sun,mon,fri;B:cat,dog;C:red
*/
------解决方案--------------------
--> 测试数据:[test]
if object_id('[test]') is not null drop table [test]
go
create table [test]([name] varchar(3),[type] varchar(1))
go
insert [test]
select 'sun','A' union all
select 'cat','B' union all
select 'dog','B' union all
select 'mon','A' union all
select 'fri','A' union all
select 'red','C'
go
declare @sql varchar(max)
with cte as
(
select [type],
rusult=stuff
(
(
select ';'+name from TEST a where a.type=test.type for xml path('')
)
,1,1,''
)
from TEST
group by [type]
)
select @sql=isnull(@sql,'')+[type]+':'+rusult+' ' from cte
print @sql
--A:sun;mon;fri B:cat;dog C:red
------解决方案--------------------
表a
name num
aa 1
bb 2
cc 4
dd 4
ee 2
一条语句实现如下:
name
aa,bb,cc,dd,ee
DECLARE @STR VARCHAR(8000)
SELECT @STR=ISNULL(@STR+',','')+name FROM (SELECT DISTINCT NAME FROM A)AS T
SELECT @STR
问题描述:
无论是在sql 2000,还是在sql 2005 中,都没有提供字符串的聚合函数,
所以,当我们在处理下列要求时,会比较麻烦:
有表tb, 如下:
id value
1 aa
1 bb
2 aaa
2 bbb
2 ccc
需要得到结果:
id values
1 aa,bb
2 aaa,bbb,ccc
即,group by id, 求value 的和(字符串相加)
1. 旧的解决方法
-- 1. 创建处理函数
CREATE FUNCTION dbo.f_str(@id int)
RETURNS varchar(8000)
AS
BEGIN
DECLARE @r varchar(8000)
SET @r = ''
SELECT @r = @r + ',' + value
FROM tb
WHERE id=@id
RETURN STUFF(@r, 1, 1, '')
END
GO
-- 调用函数
SELECt id, values=dbo.f_str(id)
FROM tb
GROUP BY id
-- 2. 新的解决方法
-- 示例数据
DECLARE @t TABLE(id int, value varchar(10))
INSERT @t SELECT 1, 'aa'
UNION ALL SELECT 1, 'bb'
UNION ALL SELECT 2, 'aaa'
UNION ALL SELECT 2, 'bbb'
UNION ALL SELECT 2, 'ccc'
-- 查询处理
SELECT *FROM (SELECT DISTINCT Id FROM @t)A
OUTER APPLY(
SELECT [values]= STUFF(REPLACE(REPLACE(
( SELECT value FROM @t N
WHERE id = A.id
FOR XML AUTO
), '<N value="', ','), '"/>', ''), 1, 1, '')
)N
/*--结果
id values
----------- ----------------
1 aa,bb
2 aaa,bbb,ccc
(2 行受影响)
--*/
--各种字符串分函数
--3.3.1 使用游标法进行字符串合并处理的示例。
--处理的数据
CREATE TABLE tb(col1 varchar(10),col2 int)
INSERT tb SELECT 'a',1
UNION ALL SELECT 'a',2
UNION ALL SELECT 'b',1
UNION ALL SELECT 'b',2
UNION ALL SELECT 'b',3
--合并处理
--定义结果集表变量
DECLARE @t TABLE(col1 varchar(10),col2 varchar(100))
--定义游标并进行合并处理
DECLARE tb CURSOR LOCAL
FOR
SELECT col1,col2 FROM tb ORDER BY col1,col2
DECLARE @col1_old varchar(10),@col1 varchar(10),@col2 int,@s varchar(100)
OPEN tb
FETCH tb INTO @col1,@col2
SELECT @col1_old=@col1,@s=''
WHILE @@FETCH_STATUS=0
BEGIN
IF @col1=@col1_old
SELECT @s=@s+','+CAST(@col2 as varchar)
ELSE
BEGIN
INSERT @t VALUES(@col1_old,STUFF(@s,1,1,''))
SELECT @s=','+C